Sero-prevalence and Impact of Selected Diseases Affecting Small Ruminants Production in Krodofan, Blue Nile and Gadarif States/ Sudan

Although certain livestock diseases have been known to play an important role in lower productivity and market access for small ruminants in the Sudan there has been few studies conducted to elucidate their exact magnitude in terms of their prevalence. Across sectional survey was therefore conducted during the period May 2005 to September 2006 to provide an overview of the most important diseases affecting small ruminants’ productivity and their economic impact. The study areas namely, Blue Nile state, Gadarif state and Elkhowie area in (W. Kordofan state) were selected according to certain criteria, namely, diversity in terms of production systems, market outlets, prevalence of poverty, dominance of sheep and goats and prevalence of major transboundary diseases. Information on small ruminants’ health and market constraints was collected through a structured questionnaire, along the market chain at seven entry points. These seven entry points, which comprised of categories of stakeholders were, villages and communities, households and flock owners, markets, traders, slaughter houses, quarantine facilities and veterinary clinics. Trained data collectors then administered questionnaires to the seven categories in each of the study states (sites). Results of interviews with small ruminants’ keepers indicated that PPR, Heartwater and Sheep pox were the most important diseases in all the study areas, with minor variations in importance on individual state level. However, heartwater and PPR had a slightly higher rank of importance in Gadarif state, sheep pox ranking third. However, PPR ranked the first in XVI importance in Blue Nile state, heartwater showing a steady importance as the second. In Elkhowei area (W. Kordofan), respondents reported Sheep pox as the most important disease, with plant poisoning ranking second. The questionnaire survey revealed that PPR was more prevalent when the production system was seasonal movement (transhumant) in both Gadarif and Blue Nile states. Further analysis revealed significant association between prevalence for each of heartwater and PPR, and winter season. There was a strong correlation between the number of animals affected with PPR and the number of sick animals that could not be sold in Blue Nile state (Pearson correlation coefficient, 0 .819), an indication that PPR was a constraint for marketing small ruminants. Similarly, there were strong positive correlations (Pearson correlation coefficients, 0.720 and 0.820 for Blue Nile and Gadarif states respectively) between the number of goats born during the year and the number that died due to PPR during the same year. This observation may be explained in terms of high susceptibility of newborns to PPR, exacerbated by poor management. MAP1-B ELIZA (Jongejan, Utreth, Netherland) was used to test 320 serum samples from a random sample of small ruminants drawn from the three study areas, to determine sero-prevalence of heartwater. Meanwhile, Competitive enzyme-linked immunosorbent assay (c- ELIZA) ((PDSL, 2005) was used to test 600 serum samples collected from small ruminants from all study sites to determine peste des petits ruminants (PPR) seroprevalence . XVII The results revealed that the sero-prevalence of heartwater was 73.1%, with a range between 12.0% and 98.5% in all the study sites. However, Gadarif state had the highest sero-positivity rate (98.5%) followed by Blue Nile state (93.3%) and ElKhowei with the lowest of all (12%). On the basis of species, sheep had 63% , while goats had a record high of 90% sero- prevalence in all the three study sites. The picture for PPR gave an overall sero-prevalence of 61.8%; while individual study states had (69.3%) in Blue Nile, (68.4%) in Elkhowei area in west Kordofan and 28.6% in Gadarif states respectively. However, the study showed higher prevalence of PPR in Elkhowei area, the pastoralists are not familiar with clinical signs of PPR and have no local name for it. Pastoralist misdiagnosis is therefore a possibility and the higher proportion of small ruminants positive for antibodies to the disease in this site would therefore imply that PPR may have been newly introduced into the area. On species basis, an overall sero-prevalence in all study sites was 62.9% for sheep and 59.7% for goats. Using chi-square statistics, there was no significant difference in seropositivity for heartwater between sheep and goats, males and females and among different age groups of each species, (p > 0.05) . With respect to PPR, and using chi-square statistics, there was significant association in the overall sero-positivity among different age groups for both species (sheep and goats). Moreover, a significant difference in seropositivity between female and male small ruminants in all study areas was observed, (p< .05). XVIII The total losses and costs resulting from identified diseases, over a period (2003, 2004, and 2005) as reported by respondents were SD. 136,483,454. PPR accounted for 29.1% while heartwater accounted for 9.9% of the losses. Since 71.98% of the respondents were entirely dependent on livestock rearing in the study areas, these losses underline the important role these diseases play in the economic wellbeing and livelihoods of poor small ruminants’ keepers. Improvement of field diagnostic facilities and use of cELISA, which is effective in the diagnosis of PPR are recommended to improve surveillance and control efforts for PPR. In addition, extension packages for small ruminants’ keepers for appropriate use of communal pastures, better recognition of diseased animals, informed usage of drugs and vaccines are highly recommended